Short description of collection: A small collection of Alan H. Barrett's papers, including chronological correspondence for 1962-1964, radio astronomy research materials from the 1950s through 1987, and a small group of photographs dated 1956 through ca. 1970.

Biography: Alan Hildreth Barrett was born in Springfield MA in 1927 and served in the U.S. Navy during World War II. He received a Bachelor of Science degree from Purdue University in 1950, then went on to Columbia University, where he did graduate work in physics under Charles Townes. He received his PhD in 1956 for a study of the microwave spectrum of the halides of indium and gallium. He was a post-doctoral fellow at the U.S. Naval Research Laboratory in 1956, where, with Edward Lilley, he made his first search for interstellar OH radicals. He was a research associate and instructor at University of Michigan from 1957-1961, and during that time made an extensive theoretical study of microwave radiation from the atmosphere of Venus. His proposed model of the Venus atmosphere and surface was confirmed by radiometric data from the Mariner II flyby mission to Venus, on which Barrett was the principle investigator, and he helped design microwave detection equipment carried on 1960-1963 Mariner missions.

In 1961 Barrett joined the Massachusetts Institute of Technology faculty as Associate Professor of Electrical Engineering, was appointed Professor of Electrical Engineering in 1965, and Professor of Physics in 1967. Much of his research at MIT was carried out in the Research Laboratory of Electronics. In 1963 Barrett and his collaborators detected, identified, and measured two 18-cm lambda-doublet lines from OH radicals in the interstellar medium, the first radio detection of molecular matter in interstellar space. The detection was a major milestone and opened the way for a new field of radio astronomy research on molecules in space. A later discovery by Barrett and colleagues that sources of OH emission were highly polarized was key evidence leading to their identification as cosmic masers.

Barrett helped develop very long baseline interferometry, and participated in the first VLBI measurements of OH radiation, thus confirming the maser hypothesis. He shared in the 1971 Rumford Prize from the American Academy of Arts and Sciences for this work. His research on molecular properties of the interstellar medium continued throughout his career.

Barrett received a Guggenheim Fellowship for study abroad in 1977-1978, was a von Humbolt Fellow in 1987, and was the Jansky Lecturer at National Radio Astronomy Observatory in 1990. He served on advisory and consulting committees to the National Aeronautics and Space Administration, the National Science Foundation, the National Institute of Health, the National Radio Astronomy Observatory, and the National Astronomy and Ionosphere Center. He was a Fellow of the American Academy of Arts and Sciences, and a member of the American Astronomical Society, the International Scientific Radio Union, and the International Astronomical Union.

Accession history: These papers from Barrett were kept by Paul Ho of Harvard-Smithsonian Center for Astrophysics, then passed on to James Moran, also at CfA, who donated them to the NRAO Archives in summer of 2015.

Publication rights: Copyright has been assigned to The National Radio Astronomy Observatory. All requests for permission to publish or quote from manuscripts must be submitted in writing to the Archivist.

Processing notes: Initial inventory of this collection was done in September 2015 by Ellen N. Bouton. Final arrangement, description, indexing, foldering and boxing of this material was begun in October 2015 and was completed in November 2015. During the processing, fasteners were removed and photocopies were made to replace thermofax sheets and newspaper clippings. Duplicates were discarded, with the exception of duplicate photos of the University of Michigan 85 foot telescope, which were sent to the University of Michigan Astronomy Department.

Scope and Contents of Collection

Correspondence Series: This series includes chronological correspondence from 1962-1964 when Barrett was at MIT. Correspondence includes discussions with colleagues about instruments and research, correspondence about students, correspondence about publications, correspondence about the 1963 detection of the OH line, and correspondence about Barrett's 1964 trip to the Soviet Union. Size: 0.5 linear feet.

Radio Astronomy Research Series: This series includes materials dated 1953-1976 on the detection of OH, on methane, on pulsars, and on Taurus B, including notes, diagrams, calculations, preprints, reprints (both collected reprints and reprints of relevant Barrett papers), photos, typescripts, and galleys. Many of the notes, diagrams, and calculations are handwritten and undated. One folder contains correspondence, meeting schedule, and conference digest for Interstellar Matter, a 1987 symposium honoring Barrett. Size: 0.5 linear feet. Related material: See also the Correspondence Series above for OH line correspondence filed there by Barrett. Click here for a folder listing, or use the NRAO Archives online catalog to search for specific items or across multiple series/collections.

Photographs Series: This series includes 44 photographs, most approximately 8x10 inches, dated ca. 1956-1970, of Barrett at the U.S. Naval Research Laboratory and University of Michigan, of the Michigan 85 foot telescope, photos thought to be from Barrett's 1964 balloon-borne radiometer observations taken at the balloon base of the National Center for Atmospheric Research, Palestine, Texas, and photos of various radio telescopes around the world. Most photographs are unlabeled and undated. Size: 0.25 linear feet.